User manual AUSTRALIAN MONITOR PA800

[. . . ] Australian Monitor f, 4aoo & fi4rzoo -) (_ -) (- Operation Manual IMPORTANT! Please read carefully. This operation manual contains important information regarding safety precautions, installation, performance, operation and maintenan e of your Piseries porcramplifier. You should familiarize yourself with the contents of this manual before operating your amplifier. Safety Precautions and Labelling The rear panelof the unit has a numberof markings and intemationally recognized symbols related to the hazards and precautions that should be taken when operating MAINS connecled equipment. The presence of a LIGHTNING FLASH with an arrowhead contained within the boundaries of a equilateral triangle is intended to alert the user that dangerous uninsulated voltages may exist within the units enclosure, These voltages may be of a sufficient magnitude as to constitute the risk of an elec- REFER SERVICING TO QUALIFIED PERSONNEL. NO USER SERVICEABLE PARTS INSIDE. The user should not attempt to service the unit. Only qualified and knowledgeable personnel familiar with the internal workings of the unit should attempt any tricalshock. This symbol is reinforced with the text: repair, servicing or authorized modification to the unit. [. . . ] You will then hear a relay "clicK, indicating mains is now directly applied to the amplifi er and the THERMAUON LED willbe green. While the ICS circuit operates there is also a 30dB mute on the signal input. Aftertwo seconds this mute will release, allowing any applied signal to pass unattenuated. When switching the amplifier off, wait a couple of seconds before switching the unit on again. This allows the ICS circuit to reset. which may be you! Before making any connections to your Piau/ Ptihzu amplifi er observe the fol lowing: 1. Ensure the mains voltage supply matches the 2. label on the rear panel of youramplifier (+/- 1 0%). Ensure that the power switch is OFF (to the left 0) Level Matching The normal operating position for the attenuator is the "0 dB" position (fully cloclwise, no attenuation). ln this position the amplifier operates at full gain. Turning the attenuator back (anticlockwise) reduces the input sensitivity by the amount marked on the attenuator scale (dial). NOTE: lf full power output is required you should operate your amplifier with the front panel attenuator above the -15d8 position, othenrise clipping of the input circuitry and its resultant distortion will occur before full output power is achieved. 3. Ensure that all system grounds 4. (earth). Avoid powering equipment within a system from multiple power sources that may be separated by largedistances. Check the continuity of all interconnecting leads short circuited conductors. to your amplifier, ensure that there are no open or 5. Ensure that the power handling of your load (speakers) can adequately cope with the power output of the amplifier. Before operat ngyour Pfuf?r'hzuamplifi er, ensure that: - Sensitivity Youramplifier is a lineardeviceoperatingwith afixed input to output voltage gain (less attenuation). The maximum output voltage sldng is determined by the applied mains voltage, load, load type and the duty cycle of the applied signal. The voltage gain factor of your amplifier is: 37 (31. 5 dB) for a PA800 45 (33. 0 dB) for a PA1200 Th e i n put The attenuators are at the'OFF' position (fully anticlockwise). The GROUND LIFT Switch is not engaged (should be in the'ouf position). The BRIDGE Switch is not engaged if you are not running the amp in bridged mode. Powering Up t REMEMBER The amplifier should be the last piece of equipment thatyou tum on and thefirst piece of equipmentthat you tum off. sensiti vity f o r y our Pr4am/?4tzu amp ifi er when the attenuator is at the "O' dB attenuation position (fully clockwise) is nominally: I We recommend tuming the attenuators on your amplifier down when turning the unit on. When you power up you +4. 0d8 load. (1 (1 . 23 volts in) for rated power into a 8 ohm . er goes through an establishment period before it will r Pfu/Prltzu, your ampl ifi +3. 0d8 load. 10 volts in) for rated power into a 4 ohm Asbalian Monitor, /tu l1 Operation Each channel of your Plw/F, hzn amplifier has a nominal balanced input impedance of 3OkOhms (@1kHz) and should not present a diffiq. rlt load for any signal source. difference between the amp earth and source equipment earth appears to the amplifief s input as a signal and is amplified as hum. There are three things you can do to avoid earth loop problems: Your signal source (i. e. the equipment feeding the amplifier) should have an output impedance of 600 Ohms or lower to avoid urnvanted loss in the cabling. h i gh freq uency 1. Ensure your mains powerforthe audio system is lnput overload occurs at +20. 5d8u (8. 25 volts). See the specification section for more detailed infor- "quiet" i. e. without equipment on it suclr as airconditioning, refrigeration or lighting whicfr may generate noise in the earth circuit. mation. 2. Ensure all equipment within the system shares a Hum Problems Most equipment is designed for minimum hum when used under ideal conditions. When connected to other equipmnt, and to safety earth in an electrically noisy environment however, problems wi ll often ocanr. common ground/ safety earth point. This will reducethe possibility of circulating earth currents as the equipment will be referenced to the same ground potential. 3. Ensure that balanced signal leads going to the amplifier are connected to earth at one end only. The three "E"s of hum and hum related noise which can plague your audio system are: Signal Ground-Lift Switch When proper system hook-up has been carried out, you may still have some hum or hum related noise. [. . . ] Give the main filter capacitors time to discharge before removing lids and inspecting the fuses. You should replacethefuse if theelement is sagging or discoloured. Only ever replace with the same type fuse and current rating. Overtime, dust may build up on the leading edge of the fan blades and reduce their cooling efficiency. The time taken forthis to happen will depend on the environment and the amount of use. When checking for a failed fuse, do not rely on visual inspection alone. [. . . ]